fabro/nodes/implement/response.md

Everything looks correct. Here's a summary of what was done:

Changes Made

File: lib/crates/fabro-workflows/src/cli/backend.rs

1. Extracted track_file_event helper function (lines 33–75)

A new recursive function that handles file-tracking logic for write_file/edit_file tool calls:

• ToolCallStarted → records the file_path argument in pending_tool_calls keyed by tool_call_id
• ToolCallCompleted (non-error) → moves the path from pending_tool_calls to files_touched and updates last_file_touched
• ToolCallCompleted (error) → removes from pending_tool_calls without recording
• SubAgentEvent → recursively unwraps the inner event and calls itself (handles arbitrarily nested sub-agents)
• Everything else → no-op

2. Refactored spawn_event_forwarder to use track_file_event

Replaced the inline match block with a single call to track_file_event(&event.event, ...), which now handles both top-level and sub-agent events.

3. Added 4 unit tests

• track_file_event_records_top_level_write — verifies basic write_file tracking still works
• track_file_event_unwraps_sub_agent_edit — verifies SubAgentEvent-wrapped edit_file calls are tracked
• track_file_event_unwraps_nested_sub_sub_agent — verifies double-nested SubAgentEvent (sub-sub-agent) is handled
• track_file_event_error_removes_pending — verifies errored sub-agent tool calls don't pollute files_touched

Verification

• ✅ cargo test -p fabro-workflows — 179 passed, 0 failed
• ✅ cargo clippy --workspace -- -D warnings — clean